Spain

Several Spanish populations lived in the New World throughout the colonial era, with their administrations being accountable to Madrid. Florida saw the first settlement, then others appeared in New Mexico, California, Arizona, Texas, and Louisiana. There were roughly 1,000 Spaniards living in the region north of Mexico in 1598, the year the first New Mexican settlement was founded; today, their descendants number around 900,000. Additional 250,000 immigrants have come to the country since its inception, either straight from Spain or after a brief stay in a Latin American nation.

The same factors that later prompted the English to settle in that region also led to the initial Spanish settlements north of Mexico (called at the time as New Spain). Imperial desires to find advanced civilizations had contributed to the growth of exploration. Additionally, the majority of Spaniards, like those on the Mayflower, migrated to the New World in search of agricultural land or, less frequently, as recent research in history has shown, freedom from religious persecution. For instance, many of the earliest people to settle in New Mexico were descended from Spanish Jews who had been forced to from Spain.

During the first part of the nineteenth century, Spanish immigration to the United States was low but consistent, but it increased in the 1850s and 1860s as a result of the social upheaval caused by the Carlist civil wars. Due to the same conditions of rural poverty and urban congestion that caused other Europeans to flee during that time, much more Spanish immigrants entered the country in the first quarter of the 20th century—27,000 in the first decade and 68,000 in the second. However, in 1921, the American government implemented a quota system that gave preference to northern Europeans, capping the number of Spaniards admitted annually at 9112, which was then lowered to 131.

In 1936 General Francisco Franco established a reactionary dictatorship that controlled Spain for 40 years beginning with the Fascist uprising against the Spanish Republic and the horrific civil war that followed. A small but notable group of liberal intellectuals fled into exile in the United States at the time of the fascist takeover. The nation experienced severe poverty for 20 years following the civil war. As a result, 44,000 Spaniards immigrated to the United States in just that decade when ties between Spain and the majority of other nations finally normalized in the middle of the 1960s. As Spain's economy began to develop in the 1970s, the numbers fell to around 3,000 annually.

In the 1980s, Europe had an economic boom, and during the course of ten years, just 15,000 immigrants from Spain were admitted. Only 76,000 Spaniards who were born abroad were counted in the 1990 U.S. census, or 4% of the country's total population. Mexicans born outside of the United States, the largest Hispanic group, comprised over two million people and made up around 21 percent of the population.